He didn't take it out. He was just wondering. But it doesn't even matter. Flash memory doesn't need a battery so even if he did take out some internal battery It would just mess with the time, and not with the mii data.

Slightly off topic but last night i formatted the Wii's system memory ( bacause someone suggested it helps with DRE's but it didn't) but before i did it i saved my Mii's to a Wii-mote and i saved the game saves to an SD card. After the format i put the Mii's and saves back on the console. I loaded up Wii sports and all my Mii's scores have been reset to zero. My kids are not happy at all that they have lost there pro status on bowling.so my question is ....What did the wii sports game save actually save ? becasue as far as i can see it was nothing.